A direct successor to the D70 Topping, the D90 benefits from the same refinements as its big brother while updating its DAC with a newer and more efficient version, the AK4499 AKM. For the rest, it largely follows the excellent internal design of the previous model and its exceptional performance.

DAC AK4499 & Accusilicon Clocks

New flagship from AKM, the AK4499 DAC chip allows precise, fast and clean conversion of high-resolution audio files. The D90 thus integrates on its digital-to-analog conversion stage an AK4499 chip with Thesycon drivers allowing transparent and rich sound reproduction and supporting PCM files up to 32bit 768kHz and DSD up to DSD512 (via USB and I2S).

The DAC is combined with a pair of AccuSilicon 451584MHz and 49.1520MHz high-end femtosecond clocks and a CPLD. These allow a perfect synchronization of the data signals for an absolutely impressive jitter attenuation.

Connectivity & Features

With its many features and connections, the D90 can be integrated into a vast majority of audio systems, offering many options for use and installation.

For its input connectivity, there are AES, USB-B (XMOS), Coaxial, Toslink Optics, and I2S LVDS via HDMI. Note that this last input has several selectable modes to adapt to your other I2S LVDS devices. On the output side, the D90 offers unbalanced RCA Stereo and balanced XLR. The D90's intelligent design allows only one or both outputs to be activated at a time.

With its integrated volume control, the D90 also acts as a preamplifier since it includes a volume controller. This volume control function can however be disabled so that the D90 can only be used as a DAC with output levels constantly at their maximums, i.e. 4Vrms for XLR output and 2Vrms for RCA output.

USB XMOS XU208 Interface & SPDIF AK4118 Receiver

For its digital interfaces, Topping once again chooses very high quality and performance by integrating into its D90 an XMOS XU208 USB chip supporting high sampling rates up to 32bit 768kHz and up to native DSD512.

For SPDIF streams, an AKM AK4118 AKM chip processes the signal with extremely low jitter. This last chip is used for the Optical, Coaxial and AES inputs and allows sampling rates up to 24bit 192kHz PCM to be achieved on the latter.

Topping D90 measurements by Audio Science Review